Needle Changing Apparatus

ABSTRACT

An apparatus is disclosed for storing and changing needles for connection with a medicament delivery device, comprising an inner housing, a reservoir disposed within the inner housing, and a needle holder disposed within the inner housing, for fluidly connecting a medicament container of the medicament delivery device with the reservoir. The apparatus also includes a plurality of patient needles displaceably disposed on the needle holder, and an outer housing displaceably disposed about the inner housing and providing a user interface to individually select one of the plurality of patient needles, connect the selected needle with the reservoir, expose the selected needle outside of the apparatus for injection, and store the selected needle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/206,438, filed on Aug. 9, 2011, which claims priority under 35 USC§119(e) from U.S. Provisional Patent Application Ser. No. 61/344,525,filed on Aug. 16, 2010, the disclosure of both of said priorapplications being incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to needles for a medicament deliverydevice, such as a pen injection device or a syringe, and moreparticularly, to a multiple needle changing apparatus for a medicamentdelivery device.

2. Description of the Related Art

Medicament delivery devices are used for self-injection of preciselymeasured doses of medication. Pen injection devices are widely used, forexample, by diabetics to self-inject insulin. A typical medicamentdelivery pen includes a cartridge that contains a volume of liquidmedication sufficient for several doses. Using a pen needle attached tothe pen injection device, the dose is injected into a tissue area, suchas the intramuscular tissue layer, the subcutaneous tissue layer, or theintradermal tissue layer.

The assembly and operation of a typical pen injection device isdescribed in commonly-assigned U.S. Patent Application Publication No.2006/0229562, published on Oct. 12, 2006, which is hereby incorporatedby reference in its entirety.

Pen injection devices, such as an exemplary pen injector 50 shown inFIGS. 1 and 2, typically comprise a dose knob/button 24, an outer sleeve13, and a cap 21. The dose knob/button 24 allows a user to set thedosage of medication to be injected. The outer sleeve 13 is gripped bythe user when injecting medication. The cap 21 is employed by the userto securely hold the pen injector 50 in a shirt pocket, purse, or othersuitable location.

FIG. 2 is an exploded view of the exemplary drug delivery pen 50 shownin FIG. 1. The dose knob/button 24 has a dual purpose and is used toboth set the dosage of the medication to be injected and to inject thedosed medicament via a lead screw 7 and stopper 15 from a medicamentcartridge 12, which is attached to the drug delivery pen through a lowerhousing 17. The medicament cartridge 12 is typically a glass tube sealedat one end with a septum 16 and at the other end with the stopper 15. Instandard drug delivery pens, the dosing and delivery mechanisms are allfound within the outer sleeve 13. Those mechanisms are not described ingreater detail herein as they are understood by those knowledgeable ofthe art.

A pen needle assembly 10 includes a hub 20, a patient needle 11extending from a patient end of the pen needle assembly, and aseptum-penetrating needle cannula 18 disposed within the hub 20 on anon-patient side thereof. The septum-penetrating needle cannula 18 is influid communication with the patient needle 11. The hub 20 is preferablyscrewed onto the lower housing 17, although other attachment means canbe used such as attaching directly to the medicament cartridge 12. Inattaching the hub 20 to the lower housing 17 or medicament cartridge 12,the septum-penetrating cannula 18 pierces the septum 16, but the septum16 does not move with respect to the medicament cartridge 12. Thestopper 15, however, is axially displaceable within the medicamentcartridge 12 while maintaining a fluid-tight seal. The distal movementof the plunger or stopper 15 within the medicament cartridge 12 (due toadvancement of the lead screw 7) causes medication to be forced into thepatient needle 11 of the hub 20.

To protect a user, or anyone who handles the pen injector 50, an outershield 29, which attaches to the hub 20, covers the hub 20. The outershield 29 can also be used as a handle or grip to screw hub 20 onto oroff of pen injector 50. An inner shield 28 covers the patient needle 11within the outer shield 29. The inner shield 28 can be secured to thehub 20 to cover the patient needle 11 by any suitable means, such as aninterference fit or a snap fit. As shown in FIG. 2, the hub 20 alsoincludes ribs 64 for engaging the outer shield 29. The outer shield 29and inner shield 28 are removed prior to use. The cap 21 fits snuglyagainst outer sleeve 13 to allow a user to securely carry the peninjection device 50.

To use the pen needle assembly 10, the user removes a sterile cover onthe outer shield 29, twists the pen needle assembly 10 onto the peninjector 50, removes the outer shield 29, and then finally removes theinner shield 28. While there are some needle storage devices that aid inplacing the pen needle assembly 10 on the pen injector 50, the userstill must remove needle hub packaging, including the inner and outershields 28 and 29, to place a needle hub onto a pen injector and readythe device for injection. This process must be repeated for eachsuccessive injection.

Pen needle assemblies are usually sold individually packaged inside aplastic cover (such as outer shield 29) with a label covering theopening in the cover to provide a sterility barrier. A need exists for aneedle dispensing and storing apparatus that stores a plurality ofneedles before and after their use.

SUMMARY OF EMBODIMENTS OF THE INVENTION

It is an aspect of the present invention to provide an apparatus forchanging needles. It is also an aspect of the present invention toprovide an apparatus for storing needles prior to their use as well assubsequent to their use. Additionally, it is an aspect of the presentinvention to provide an apparatus for changing needles for connectionwith a medicament delivery device.

The foregoing and/or other aspects of the present invention are achievedby providing an apparatus for storing and changing needles forconnection with a medicament delivery device, including an innerhousing, a reservoir disposed within the inner housing, and a needleholder disposed within the inner housing, for fluidly connecting amedicament container of the medicament delivery device with thereservoir. The apparatus also includes a plurality of patient needlesdisplaceably disposed on the needle holder, and an outer housingdisplaceably disposed about the inner housing and providing a userinterface to individually select one of the plurality of patientneedles, connect the selected needle with the reservoir, expose theselected needle outside of the apparatus for injection, and store theselected needle.

The foregoing and/or other aspects of the present invention are alsoachieved by providing a method of selecting a needle for a medicamentdelivery device having a medicament container, including the operationsof connecting the medicament delivery device to an apparatus for storingand changing needles, establishing fluid communication between themedicament container and a reservoir within an inner housing of theapparatus, and rotating an outer housing of the apparatus relative tothe inner housing to select one of a plurality of needles movablydisposed on a needle holder, which is disposed within the inner housing.The method also includes the operations of axially displacing the outerhousing relative to the inner housing in a distal direction away fromthe medicament delivery device, thereby fluidly connecting a selectedone of the plurality of needles with the reservoir and exposing apatient end of the selected needle outside of the apparatus, and axiallydisplacing the outer housing in a proximal direction to re-sheath theselected needle within the inner housing.

The foregoing and/or other aspects of the present invention are alsoachieved by providing an apparatus for storing and changing needles forconnection with a medicament delivery device, including an innerhousing, a reservoir disposed within the inner housing, and a needleholder disposed within the inner housing, for fluidly connecting amedicament container of the medicament delivery device with thereservoir. The apparatus also includes a plurality of patient needlesdisplaceably disposed on the needle holder, and an outer housingrotatable relative to the inner housing for selecting one of theplurality of patient needles, and axially displaceable relative to theinner housing for connecting the selected needle with the reservoir,exposing the selected needle outside of the apparatus for injection, andre-sheathing the selected needle within the inner housing.

Additional and/or other aspects and advantages of the present inventionwill be set forth in part in the description that follows and, in part,will be apparent from the description, or may be learned by practice ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects and advantages of embodiments of theinvention will become apparent and more readily appreciated from thefollowing detailed description, taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a perspective view of an exemplary drug delivery pen;

FIG. 2 is an exploded view of the exemplary drug delivery pen of FIG. 1;

FIG. 3 is a perspective view of a needle changing device in accordancewith an embodiment of the present invention;

FIG. 4 is an exploded perspective view of the needle changing device ofFIG. 3;

FIG. 5 is a perspective view in cross-section taken along line 5-5 inFIG. 3 of the needle changing device of FIG. 3;

FIG. 6 is a perspective view of a needle of the needle changing deviceof FIG. 3;

FIGS. 7-11 are perspective views illustrating alternative embodiments ofneedles of the needle changing device of FIG. 3;

FIG. 12 is a perspective view in cross-section of a needle changingdevice in accordance with an embodiment of the present inventionemploying the needle of FIG. 11;

FIG. 13 is a perspective view of the pen injector of FIG. 1 and theneedle changing device of FIG. 3 prior to the coupling thereof;

FIGS. 14-16 are perspective views of the coupled pen injector of FIG. 1and the needle changing device of FIG. 3 illustrating an overview of theoperation thereof;

FIGS. 17-29 are perspective partial cutaway views illustrating theoperation of the needle changing device of FIG. 3 in more detail;

FIGS. 30 and 31 are perspective views in cross-section of a firstalternative sterility barrier for the needle changing device of FIG. 3;

FIG. 32 is a perspective view in cross-section of a second alternativesterility barrier for the needle changing device of FIG. 3;

FIG. 33 is a perspective view in cross-section and FIG. 34 is aperspective view, together illustrating a third alternative sterilitybarrier for the needle changing device of FIG. 3;

FIGS. 35 and 36 are perspective views in cross-section of a fourthalternative sterility barrier for the needle changing device of FIG. 3;

FIG. 37 is a perspective view of a septum plate;

FIG. 38 is a perspective view in cross-section of the fourth alternativesterility barrier for the needle changing device of FIG. 3 employing theseptum plate of FIG. 37;

FIGS. 39-42 are perspective views in cross-section of a fifthalternative sterility barrier for the needle changing device of FIG. 3;

FIGS. 43 and 44 are perspective views in cross-section of a sixthalternative sterility barrier for the needle changing device of FIG. 3;

FIGS. 45 and 46 are perspective views in cross-section of a seventhalternative sterility barrier for the needle changing device of FIG. 3;

FIGS. 47 and 48 are perspective views in cross-section of an eighthalternative sterility barrier for the needle changing device of FIG. 3;

FIG. 49 is a partial perspective view in cross-section of a ninthalternative sterility barrier for the needle changing device of FIG. 3;

FIG. 50 is a perspective view in cross-section of a tenth alternativesterility barrier of the needle changing device of FIG. 3;

FIG. 51 is a perspective view in cross-section of an eleventhalternative sterility barrier of the needle changing device of FIG. 3;

FIG. 52 is a perspective view in cross-section of a twelfth alternativesterility barrier of the needle changing device of FIG. 3;

FIG. 53 is a perspective view of a pen injection device and a needlechanging device according to another embodiment of the presentinvention;

FIG. 54 is a perspective view of the needle changing device of FIG. 53;

FIG. 55 is an exploded perspective view of the needle changing device ofFIG. 53;

FIG. 56 is a perspective view in cross-section of the needle changingdevice of FIG. 53;

FIG. 57 is a perspective view of a needle of the needle changing deviceof FIG. 53;

FIG. 58 is a perspective bottom view of a channel disk of the needlechanging device of FIG. 53;

FIG. 59 is a top perspective view in cross-section of an adapter channelof the needle changing device of FIG. 53; and

FIG. 60 is a final needle for use with the needle changing device ofFIG. 3 or the needle changing device of FIG. 53.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE PRESENT INVENTION

Reference will now be made in detail to embodiments of the presentinvention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments described herein exemplify, but do notlimit, the present invention by referring to the drawings. As will beunderstood by one skilled in the art, terms such as up, down, bottom,and top are relative, and are employed to aid illustration, but are notlimiting.

FIG. 3 is a perspective view of a needle changing device 100 adapted tobe connected to a pen injector (not shown) in accordance with anembodiment of the present invention. For brevity, the phrase “changingdevice 100” will be used hereinafter instead of “needle changing device100.” As shown in FIG. 3, the changing device 100 includes an outerhousing 104, an inner housing 108, and a counter ring retainer 112. Theouter housing 104 provides a user interface and is movably disposed withrespect to the inner housing 108. The counter ring retainer 112 retainsa needle counter or counter ring 116 (described in greater detail below)and has a window 120 disposed therein for viewing the number ofremaining unused needles in the changing device 100.

FIG. 4 is an exploded perspective view of the changing device 100. Inaddition to the outer housing 104, the inner housing 108, and thecounter ring retainer 112, as shown in FIG. 4, the changing device 100also includes a needle counter 116 the needle holder 124 plurality ofneedles 128 (though only a single needle 128 as shown in FIG. 4 forclarity), a self-sealing annular reservoir septum 132, a reservoir plate136, and a self-sealing patient end septum 140. The reservoir plate 136has a recess therein that, in conjunction with the reservoir septum 132,forms a reservoir 148.

Though not shown in FIG. 4, and described in greater detail below, theneedle holder 124 also includes a lumen member or septum penetratingneedle cannula 144 (visible in FIG. 5) for connecting the reservoir 148with a medicament cartridge of a pen injector, such as the medicamentcartridge 12 of the pen injector 50. Though one of ordinary skill in theart will understand that other pen injectors may be used, for brevity,hereinafter, the pen injector 50 will be used as an exemplary peninjector.

A method for assembling the changing device 100 includes the operationsof inserting the reservoir septum 132 into a bottom of the needle holder124, and inserting the reservoir plate into the needle holder 124 andonto the reservoir septum 132 to form the reservoir 148. The method alsoincludes the operations of inserting a plurality of needles 128 onto theneedle holder 124, inserting the patient ends of the plurality ofneedles 128 into the patient end septum 140, inserting the counter ring116 and the counter ring retainer 112 onto a top of the needle holder124, inserting the needle holder 124 into the inner housing 108 suchthat the patient end septum 140 is disposed at a patient ends thereof,and inserting the inner housing 108 and the counter ring retainer 112within the outer housing 104.

FIG. 5 is a perspective view in cross-section taken along line 5-5 inFIG. 3 of the changing device 100. FIG. 5 illustrates a plurality ofneedles 128 arrayed circumferentially around the outside of the needleholder 124. As shown in FIG. 5, the reservoir plate 136, in conjunctionwith the reservoir septum 132 forms the reservoir 148. A non-patient endof the changing device 100 includes a space 152 for connecting the peninjector 50 to the changing device 100 for example, by employingthreading 156 to screw the pen injector 50 into the changing device 100.Additionally, the septum penetrating needle cannula 144 fluidly connectsthe reservoir 148 with space 152. When the pen injector 50 is connectedto the changing device 100, the septum penetrating needle cannula 144fluidly connects the reservoir 148 with the medicament cartridge 12.

Further, as shown in FIG. 5, the patient end septum 140 is disposed at apatient end of the changing device 100. During storage, both before andafter use, the patient ends of the respective needles 128 are disposedwithin the patient end septum 140. Thus, the patient end septum 148provides a sterility barrier for the needles 128. Similarly, both beforeand after use, the non-patient end of the respective needles 128 aredisposed within the reservoir septum 132, thereby providing a sterilitybarrier.

As shown in FIG. 6, the ear-shaped needle 128 includes a patient portion160, a septum penetrating portion 164, and a connecting portion 168fluidly connecting the septum penetrating portion 164 and the patientportion 160. Both the patient portion 160 and the septum penetratingportion 164 point in substantially the same direction. In other words,the patient portion 160 and the septum penetrating portion 164 aresubstantially parallel to each other, and are oriented in substantiallythe same direction. Put another way, the patient portion 160 and theseptum penetrating portion 164 both point toward the patient end of thechanging device 100.

Referring back to FIG. 5, because of the above-described needlegeometry, the reservoir septum 132 is reversed with respect to thedirection of a typical cartridge septum. Thus, the septum penetratingportion 164 penetrates the reservoir septum 132 from above. As shown inFIG. 6 and as described in greater detail below, an exterior side (withrespect to the needle holder 124) of the connecting portion 168 hasupper and lower needle protrusions 172 and 174 disposed thereon.

According to one embodiment, both the patient portion 160 and thepenetrating portion 164 are formed of metal, for example, steel orstainless steel. Alternatively, the patient portion 160 and thepenetrating portion can be formed of plastic. Additionally, according toone embodiment, the connecting portion 168 is formed of plastic, forexample, polypropylene (PP) or polyethylene (PE). Further, according toone embodiment, the connecting portion 168 is integrally formed as asingle unit by suspending patient portion 160 and the penetratingportion 164 in the connecting portion 168, for example, by amedical-grade adhesive.

FIGS. 7-10 are perspective views illustrating alternative embodiments ofneedles of the changing device 100. In FIG. 7, two opposing side pieces176 and 178 are sealed together capturing a septum needle 180 and apatient needle 184. The septum needle 180, because it does not interfacewith the patient, can be formed of metal or, alternatively, of plastic.Further, in an alternative embodiment (not shown), a plastic septumneedle 180 can be integrated into either of the two opposing side pieces176 and 178, or mating halves of a plastic septum needle 180 can bedisposed on the side pieces 176 and 178. The side pieces 176 and 178each have the recessed channels therein. When the side pieces 176 and178 are sealed together (for example, by a medical-grade adhesive, orheat, or radiation) the recesses form a fluid path between the septumneedle 180 and the patient needle 184.

FIG. 8 illustrates an embodiment in which a needle receptacle 188 isover-molded onto a bent needle 192. As shown in FIG. 9, a tube 196providing a fluid pathway between a septum needle 200 and a patientneedle 204 clips into a recess 208 of a needle receptacle 212. The twoneedles are bonded to the tube 196 or, alternatively, to the receptacle212. In FIG. 10, thin halves 216 and 220 are bonded over a septum needle224 and a patient needle 228 establishing a fluid path therebetween, andproducing needle 232.

FIG. 11 is a perspective view of another alternative embodiment of aneedle for the changing device 100. As shown in FIG. 11, the needle 232is a single needle with a septum end 236 and a patient end 240. Theseptum end 236 is for piercing the reservoir septum 132, thereby fluidlyconnecting the reservoir 148 and the patient end 240. The needle 232also includes a needle receptacle 244 for moving the needle 232 relativeto the reservoir 240. FIG. 12 is a perspective view in cross-section ofa needle changing device in accordance with an embodiment of the presentinvention employing the needle of FIG. 11. FIG. 12 illustrates a stateof the changing device 100 prior to deployment of the needle 232. Asshown in FIG. 12, the septum end 236 of the needle 232 penetrates thereservoir septum 132 and the patient end 240 penetrates the patient endseptum 140. Additionally, the outer housing 104 is engaged with theneedle receptacle 244 and thus, as will be described in greater detailbelow, the needle 232 is ready for deployment.

FIG. 13 is a perspective view of the pen injector 50 and the changingdevice 100 prior to the coupling thereof. To connect the pen injector 50with the changing device 100, according to one embodiment, the userthreads the pen injector 50 into the changing device 100 using, forexample, screw threads 156.

FIGS. 14-16 are perspective views of the coupled pen injector 50 and thechanging device 100 illustrating an overview of the operation thereof.As shown in FIG. 14, the user first rotates the outer housing 104 toselect an unused needle, for example needle 128 or needle 232.Subsequently, as shown in FIG. 15 the user moves the outer housing 104axially away from the pen injector 50, thereby exposing needle 128. Inother words, the user slides the outer housing 104 down, or distallywith respect to the pen injector 50 to expose the needle 128. Afterdispensing the medicament, as shown in FIG. 16, the user moves the outerhousing 104 toward the pen injector 50, thereby re-sheathing the needle128. Put another way, the user slides the outer housing 104 up, orproximally with respect to the pen injector 50 to withdraw the needle128, thereby effectively and safely storing the used needle 128.

Operation of the changing device 100 will now be discussed in moredetail with respect to FIGS. 17-29. As shown in FIG. 17, the needleholder 124 includes a plurality of axial slots 248 arrayed radiallyaround the needle holder 124. The counter ring retainer 112 includes ananti-rotation member 252. According to one embodiment, the anti-rotationmember 252 comprises a cantilevered arm 256 having a locking head 260disposed at a free end thereof. The outer housing 104 is coupled with aprotrusion 264 (see, for example, FIG. 4) of the counter ring retainer112 so that the counter ring retainer 112 rotates along with the outerhousing 104. As the user rotates the outer housing 104 to select thenext unused needle 128, the anti-rotation member 252 slides into theaxial slot 248 corresponding to the next unused needle 128. Morespecifically, under the bias of the cantilevered arm 256, the lockinghead 260 slides into and engages the axial slot 248, as shown in FIG.18. The engagement of the locking head 260 with the axial slot 248prevents circumferential rotation of the outer housing 104 and thecounter ring retainer 112.

Also shown in FIG. 18 (as well as FIG. 3), the outer housing 104includes an engagement arm 268 for selectively engaging portions of theneedle 128. As shown in FIG. 19, the engagement arm 268 has a tooth 272.The tooth 272 has a top 276 and a bottom 280. The top 276 issubstantially flat and the bottom 280 has a flat portion and a beveledportion. As the user moves the outer housing axially away from the peninjector 50, as shown in FIG. 20, the flat portion of the bottom 280 ofthe tooth 272 engages the top of lower needle protrusion 174 (also shownin FIG. 6) and thereby drives the needle 128 axially away from the peninjector 50. This axial motion of the needle 128 causes the septumpenetrating portion 164 of the needle 128 to penetrate all the waythrough the reservoir septum 132 into the reservoir 148.

Additionally, this axial motion of the needle 128 causes the patientportion 160 of the needle 128 to penetrate all the way through thepatient end septum 140 and extend outside of the changing device 100, asshown in FIG. 21. Thus, the axial stroke of the outer housing 104established fluid connection between the patient portion 160 and thereservoir 148. According to one embodiment, the patient portion 160 ofthe needle 128 has a lubricant disposed thereon for easing injectioninto a patient. Also illustrated in FIG. 21, the inner housing 108includes a plurality of slots 284 to guide axial movement of the needle128. Additionally, the exposed patient portion 160 of the needle 128 isradially displaced with respect to a center of the changing device 100.In other words, the exposed patent portion of the needle 128 is offsetfrom the center.

Once the patient portion 160 of the needle 128 is completely extended,as the user continues to move the outer housing 104 axially away fromthe pen injector 50, as shown in FIG. 22, the beveled portion of thebottom 280 of the tooth 272 causes the tooth 272 of the engagement arm268 to slide over the lower needle protrusion 174. Once the tooth 272clears the bottom of the lower needle protrusion 174, the cantileveredengagement arm 268 snaps back radially inwardly so that the top 276 ofthe tooth 272 engages the bottom of the lower needle protrusion 174, asshown in FIG. 23.

On the first use of the changing device 100, the user primes the device100 to express one, or a few drops of the medicament from the patientportion 160 of the needle 128, to test the fluid path and to ensure thatthere are no air bubbles in the fluid path. This priming charges thechamber 148, and thus further priming during the use of the device 100is substantially unnecessary. To minimize wasting medicament duringpriming, the volume of the reservoir 148 is minimized. Once the outerhousing 104 reaches the bottom of its stroke, the user injects thedesired volume of medicament.

As shown in FIG. 24, a lower portion of the outer housing 104 has aplurality of relief slots 288 so that as the outer housing 104 reachesthe bottom of its stroke, the lower portion of the outer housing 104passes over a circumferential hub 292 of the inner housing 108 andelastically deforms radially outwardly. This elastic deformation biasesthe outer housing 104 to ease the subsequent upward motion (axiallytoward the pen injector 50) of the outer housing 104.

Subsequent to administering the medicament, the user moves the outerhousing 104 axially toward the pen injector 50 to re-sheath the patientportion 160 of the needle 128 within the patient end septum 140 anddisplace the septum penetrating portion 164 relative to the reservoirseptum 132, so that the septum penetrating portion 164 of the needle 128no longer extends into the reservoir 148.

Turning to FIG. 25, as the user moves the outer housing 104 axiallytoward the pen injector 50, due to engagement between the engagement arm268 and the bottom of the lower needle protrusion 174, the top of upperneedle protrusion 172 engages a lower portion 296 of the protrusion 264of the counter ring retainer 112. According to one embodiment, the lowerportion 296 of the protrusion 264 is cantilevered. As shown in FIG. 25,the lower portion 296 has a beveled portion 300 and a retaining portion304. As the outer housing 104 moves the needle 128 axially toward thepen injector 50, the top of the upper needle protrusion 172 engages thebeveled portion 300, deflecting (i.e., elastically deforming) theprotrusion 264 to displace the lower portion 296 radially outwardly.

With further axial upward motion of the needle 128, as the outer housing104 reaches the top of its stroke, the upper needle protrusion 172passes the lower portion 296 of the protrusion 264, which snaps backradially inwardly to so that the retaining portion 304 engages thebottom of the upper needle protrusion 172, as shown in FIG. 26.Additionally, this further axial upward motion of the needle 128 causesthe top of the needle 128 to engage and displace the locking head 260 ofthe anti-rotation member 252 of the counter ring retainer 112, therebydisengaging the locking head 260 from its locked position with respectto the axial slot 248.

Further, though omitted from FIG. 26 for clarity, as shown in FIG. 27,as the outer housing 104 reaches the top of its stroke, the top of theneedle 128 is retained by a retaining clip 308 of the inner housing 108to retain the used needle 128 in an axially raised position with respectto the remaining unused needles 128 (see FIG. 26 for relativepositioning of used needle 128 and unused needles 128). Retention of theneedle 128 by the retaining clip 308 prevents the needle 128 from beingselected as the next unused needle, and thereby prevents reuse of theneedle 128.

Referring to FIG. 28, because the locking head 260 has been freed fromthe locking position with respect to the axial slot 248 by the upwardaxial movement of the needle 128, the user is once again permitted tocircumferentially rotate the outer housing 104 and the counter ringretainer 112. When the user rotates the outer housing 104 and thecounter ring retainer 112, a beveled face 312 of the locking head 260contacts the side of the axial slot 248, moving the locking head upwardand energizing the cantilevered arm 256. Once the locking head 260clears the edge of the axial slot 248, continued rotation of the outerhousing by the user moves the anti-rotation member 252 to the next axialslot, to select the next unused needle 128, as shown in FIG. 29.

According to one embodiment, the user rotates the outer housing 104approximately 15° to select the next unused needle 128. One skilled inthe art will understand, however, that other increments of rotation maybe employed without departing from the scope of the invention.Additionally, although in the above-described embodiment adjacentneedles 128 are sequentially selected, one skilled in the art willunderstand that sequentially selected needles need not be adjacent. Forexample, every other, or every third needle 128 may be selected as thenext unused needle to permit a greater range of rotation of the outerhousing to accommodate a desired patient feel to the patient interface.In such an embodiment, two or three full rotations of the outer housingmay be used to exhaust all the unused needles. Numbering of the needleson the needle counter would, of course, need to be alteredappropriately.

Further, although, the numbering system in the above-describedembodiment counts upward with respect to the number of needles, it willbe understood that the changing device 100 may, without departing fromthe scope of the present invention, count downward, reflecting thenumber of unused needles remaining.

FIGS. 30 and 31 are perspective views in cross-section of a firstalternative sterility barrier for the changing device 100. As shown inFIG. 30, a respective plurality of tubes 316 is disposed around bottomportions of the plurality of needles 128. An inner septum 320 isdisposed at a bottom of the inner housing 108, and a non-resealingmembrane 324 covers the bottom of the inner septum 320. The inner septum320 has an annular snap 328 that secures the inner septum 320 within aguide 332. The guide 332 has holes therethrough to guide the tubes 316when they pass through the guide 332.

In operation, prior to deployment, each tube 316 covers a part of theneedle 128 that does not penetrate skin so that the sterile patientportion 160 is only exposed to air. Upon deployment, the tube 316 movesdown along with the needle 128 as the needle 128 is exposed outside ofthe changing device 100. The bottom of the tube 316 remains embedded inthe inner septum 320 as the patient portion 160 continues its downwardmovement to pierce the membrane 324 and be exposed outside the changingdevice 100. Subsequently, as the needle 128 is moved axially toward thepen injector 50, as shown in FIG. 31, the tube 316 remains embedded inthe inner septum 320, shielding the unused needles from beingcontaminated.

FIG. 32 is a perspective view in cross-section of a second alternativesterility barrier for the changing device 100. Similar to the embodimentof FIGS. 30 and 31, an inner septum 336 is disposed at a bottom of theinner housing 108, and a non-resealing membrane 340 covers the bottom ofthe inner septum 336. Additionally, the inner septum 336 has an annularsnap 344 that secures the inner septum 336 within a guide 348. The guide348 has holes therethrough to guide the needles 128. Further, aplurality of tubes 352 corresponds to the plurality of needles 128. Thetubes 352, however, are connected by at least one band 356, and arefixedly disposed in the inner septum 336. Because the tubes 352 arefixedly disposed in the inner septum 336, the tubes 352 shield theunused needles 128 from being contaminated. In operation, the needles128 move relative to the fixed tubes 352.

FIG. 33 is a perspective view in cross-section and FIG. 34 is aperspective view, together illustrating a third alternative sterilitybarrier for the changing device 100. As shown in FIG. 33, the patientportion 160 of the needle 128 is housed within a hollow cylinder 360that contacts a soft septum 364 on the bottom of the inner housing 108.Upon activation, as shown in FIGS. 33 and 34, the cylinder 360 piercesthrough the membrane or septum 364, opening a path for the patientportion 160 to be exposed. The patient portion 160 does not contact thecylinder 360. According to one embodiment shown in FIG. 34, the septum364 has a + or x-shaped (cruciform) perforation to ease the piercing.

FIGS. 35 and 36 are perspective views in cross-section of a fourthalternative sterility barrier for the changing device 100. As shown inFIG. 35, a plurality of sharp features 368 is disposed on a floor of theinner housing 108. The floor of the inner housing 108 has a hole 370therethrough corresponding to the interior of each sharp feature 368.The sterility barrier around the patient portion 160 is a rigid plasticshell 372 that does not contact the patient portion 160. The rigidplastic shell 372 may be made of, for example, PE or PP. In operation,as shown in FIG. 36, as the user moves the needle 128 axially away fromthe pen injector 50 via the outer housing 104, the sharp feature 368pierces the shell 372 and the patient portion 160 extends through thehole 370.

According to one embodiment, the sharp features 368 and shell 372 aresimilarly applied to the septum penetrating portion 164. For example, asshown in FIG. 37, an annular septum plate 374 disposed on top ofreservoir septum 132 has a plurality of sharp features 368 disposedthereon. In this embodiment, the sharp features are frusta, or truncatedcones. One skilled in the art will understand that other shapes arepossible for the sharp features without departing from the scope of theinvention. In operation, as shown in FIG. 38, as the user moves theneedle 128 axially away from the pen injector 50 via the outer housing104, the sharp feature 368 pierces the shell 372 and the septumpenetrating portion 164 extends into and through the self-sealingreservoir septum 132.

FIGS. 39-42 are perspective views in cross-section of a fifthalternative sterility barrier for the changing device 100. FIGS. 39-42illustrate a rigid plastic sterility barrier 376 that breaks part duringneedle engagement with the floor of the inner housing 108. The rigidplastic barrier 376 may be made of, for example, PE or PP. According toone embodiment, the barrier 376 is integral to a hub of the patientportion 160 via living hinges. According to one embodiment, thesterility barrier 376 is similarly applied to the septum penetratingportion 164, with the reservoir septum 132 functioning in a similarmanner to the floor of the inner housing 108, except that there is nopre-existing hole in the reservoir septum 132.

FIGS. 43 and 44 are perspective views in cross-section of a sixthalternative sterility barrier for the changing device 100. As shown inFIG. 43, the patient portion 160 has a hub 380 disposed thereon, and thehub 380 has a sterility barrier 384 slidably disposed thereon. Inoperation, as shown in FIG. 44, as the barrier 384 contacts the floor ofthe inner housing 108 when the user moves the needle 128 axially awayfrom the pen injector 50 via the outer housing 104, the barrier 384collapses by sliding up the hub 380. As the barrier 384 collapses, thepatient portion 160 pierces through the barrier 384 and extends througha hole 388 in the floor of the inner housing 108. According to oneembodiment, the hub 380 and barrier 384 are similarly applied to theseptum penetrating portion 164, with the reservoir septum 132functioning in a similar manner to the floor of the inner housing 108,except that there is no pre-existing hole in the reservoir septum 132.

FIGS. 45 and 46 are perspective views in cross-section of a seventhalternative sterility barrier for the changing device 100. As shown inFIG. 45, the patient portion 160 has a hub 392 disposed thereon, and thehub 392 has a sterility barrier 396 disposed thereon. In operation, asshown in FIG. 46, as the barrier 396 contacts the floor of the innerhousing 108 when the user moves the needle 128 axially away from the peninjector 50 via the outer housing 104, the barrier 396 collapses and thepatient portion 160 pierces through the barrier 396, extending throughthe hole 388 in the floor of the inner housing 108. According to oneembodiment, the hub 392 and barrier 396 are similarly applied to theseptum penetrating portion 164, with the reservoir septum 132functioning in a similar manner to the floor of the inner housing 108,except that there is no pre-existing hole in the reservoir septum 132.

FIGS. 47 and 48 are perspective views in cross-section of an eighthalternative sterility barrier for the changing device 100. As shown inFIG. 47, the patient portion 160 has a hub 400 disposed thereon, and thehub 400 has a sterility barrier 404 disposed thereon. The barrier 404includes a bellows 408 and an end piece 412. According to oneembodiment, the end piece 412 is made of paper. In operation, as shownin FIG. 48, as the barrier 404 contacts the floor of the inner housing108 when the user moves the needle 128 axially away from the peninjector 50 via the outer housing 104, the bellows 408 collapses and thepatient portion 160 pierces through the end piece 412, extending throughthe hole 388 in the floor of the inner housing 108. According to oneembodiment, the sterility barrier 404 is similarly applied to the septumpenetrating portion 164, with the reservoir septum 132 functioning in asimilar manner to the floor of the inner housing 108, except that thereis no pre-existing hole in the reservoir septum 132.

FIG. 49 is a partial perspective view in cross-section of a ninthalternative sterility barrier 416 for the changing device 100, in whichthe sterility barrier 416 is cut away during rotation of the outerhousing 104. According to one embodiment, the barrier 416 is a paperbarrier 416. As shown in FIG. 49, the outer housing 104 has a cuttingarm 420 extending down into the inner housing 108. For clarity, only asingle needle 128 is shown. The cutting arm 420 has a blade 424 disposedat a distal end thereof. During rotation of the outer housing 104, theblade slices open, or peels off the sterility barrier 416 of the nextunused needle 128.

FIG. 50 is a partial perspective view in cross-section of a tenthalternative sterility barrier 428 for the changing device 100. Forclarity, the patient end of only a single needle 128 is shown. Thesterility barrier 428 includes a sterile floor 432 disposed at a distalend of the inner housing 108, the needle hub 436 disposed around aportion of the patient end of the needle 128, and introducer 440.According to one embodiment, sterile floor 432 is a septum 432.Alternatively, the sterile floor 432 the floor of a plastic housing, athin, pierceable foil, or a trapped piece of foil or film. Theintroducer 440 has a shoulder 444 and at least one inwardly protrudingcircumferential protrusion 448 that selectively engages acircumferential depression 452 in the needle hub 436. Additionally, theintroducer 440 has a beveled distal cutting tip or chisel 456. Theintroducer 440 may be made of, for example, metal or plastic.

Shown in mid-operation in FIG. 50, as the needle 128 is distallydisplaced, because of the frictional engagement between thecircumferential protrusion 448 and the circumferential depression 452,the distal cutting tip 456 cuts through the portion of the sterile floor432. Subsequent to this cutting, once the shoulder 444 engages thesterile floor 432 with the continued distal displacement of the needle128, further distal displacement of the needle 128 results in thecircumferential depression 452 disengaging with the circumferentialprotrusion 448, and needle hub 436 displacing distally relative to theintroducer 440, thereby exposing the distal end of the needle 128outside of the changing device 100. As the needle 128 is re-sheathedwithin the inner housing 108, the needle hub 436 and the introducer 440maintain the relative positions that they possessed at the distal end ofthe needle's stroke.

According to one embodiment, the distal cutting tip 456 of theintroducer 440 is disposed around the circumference of the distal end ofthe introducer 440. According to another embodiment, the distal cuttingtip 456 is disposed only around a portion of the circumference (forexample, 180° or 270°) of the distal end of the introducer 440. In suchan embodiment, the introducer 440 cuts a flap that folds out of the waywhen the needle 128 is exposed outside of the device 100. Such anembodiment also prevents particulate (for example, a piece entirely cutout of the sterile floor 432) from falling out of the changing device100.

FIG. 51 is a partial perspective view in cross-section of an eleventhalternative sterility barrier 460 for the changing device 100. Forclarity, the patient end of only a single needle 128 is shown. Thesterility barrier 460 includes a needle hub 464 disposed around aportion of the patient and of the needle 128, an introducer 468, and aboot 472. The needle hub 164 includes at least one circumferentialdepression selectively engaged with a corresponding circumferentialprotrusion 480 on the introducer 468. The introducer 468 also has ashoulder 484 and a beveled distal cutting tip or chisel 488.

As shown in FIG. 51, the floor of the inner housing 108 has an opening492 therethrough corresponding to each of the plurality of needles 128.The openings 492 are radially spaced from a central axis of the innerhousing 108.

Shown in mid-operation in FIG. 51, as the needle 128 is distallydisplaced, because of the frictional engagement between thecircumferential protrusion 480 and the circumferential depression 476,as well as the frictional engagement between the introducer 468 and theboot 472, the sterility barrier 460 travels with needle 128 until theboot 472 contacts the floor of the inner housing 108.

With continued distal displacement of the needle 128, the frictionbetween the boot 472 and the introducer 468 is overcome and the distalcutting tip 488 cuts the floor of the boot 472 and travels distallyalong with the needle 128 until the shoulder 484 contacts a proximal andof the boot 472. With further distal displacement of the needle 128, thefriction between the circumferential depression 476 and thecircumferential protrusion 480 is overcome and the distal end of theneedle 128 is exposed outside of the changing device 100 through theopening in the boot 472 cut by the distal cutting tip 488 and throughthe opening 492 in the floor of the inner housing 108. As the needle 128is re-sheathed within the inner housing 108, the needle hub 464,introducer 468, and the boot 472 maintain the relative positions thatthey possessed at the distal end of the needle's stroke.

FIG. 52 is a partial perspective view in cross-section of a twelfthalternative sterility barrier 500 for the changing device 100. Forclarity, the patient end of only a single needle 128 is shown. Thesterility barrier 500 includes a boot 504. As shown in FIG. 52, thefloor of the inner housing 108 has an opening 508 therethroughcorresponding to each of the plurality of needles 128. The openings 508are radially spaced from the central axis of the inner housing 108.

Shown in mid-operation in FIG. 52, as the needle 128 is distallydisplaced, the boot 504 travels with needle 128 until the boot 504contacts the floor of the inner housing 108. With further distaldisplacement, the needle 128 pierces the boot 500 and exposed outside ofthe changing device 100 through the opening 508. According to oneembodiment, the floor of the inner housing 108 also includes a collar512 with a beveled proximal edge for guiding the boot 504. As the needle128 is re-sheathed within the inner housing 108, the boot 504 maintainsthe relative position that it possessed at the distal end of theneedle's stroke.

FIG. 53 is a perspective view of the pen injector 50 and a needlechanging device 520 (for brevity, hereinafter changing device 520)according to another embodiment of the present invention. Compared withthe changing device 100, the changing device 520 has a smaller profile.For convenient storage, a cap 524 covers the changing device 520 whilethe changing device 520 is connected to the pen injector 50.

FIG. 54 is a perspective view of the changing device 520, FIG. 55 is anexploded perspective view of the changing device 520, and FIG. 56 is aperspective view in cross-section of the changing device 520. As shownin FIGS. 54, 55, and 56, the changing device 520 includes an adapter 524connecting the changing device 520 with the pen injector 50, outerhousing 536, and an inner housing 540. The outer housing 536 rotates andaxially displaces relative to the inner housing 540. The bottom floor544 of the inner housing 540 includes a plurality of openings 548therethrough respectively corresponding to a plurality of needles 552disposed within the inner housing 540.

Additionally, the changing device 520 includes an adapter cannula 532connected with the adapter 528, a top septum 556, a channel disk 560, anadapter channel 564, and a reservoir septum 568. Other details of thechanging device 520, such as the needle counter and needle selectingmechanisms, are omitted for brevity and clarity. Other than the notedexceptions described in greater detail below, the changing device 520functions substantially similarly to the changing device 100 describedabove.

FIG. 57 is a perspective view of needle 552 of the changing device 520.Most notably, in comparison with the needle 128, the needle 552substantially straight. The needle 552 includes a septum portion 572 forpiercing the reservoir septum 568 and communicating with reservoir, ahub or engaging portion 576 for interacting with the selectingmechanism, and a patient portion 580 in fluid communication with theseptum portion 572, for piercing a patient's skin. According to oneembodiment, the proximal end of the needle 552 is open for communicationwith a reservoir 604 described in greater detail below. According toanother embodiment, the proximal end of the needle 552 is closed, and aside opening is disposed distally spaced from the proximal end of theneedle 552 for communication with the reservoir 604.

FIG. 58 is a perspective bottom view of the channel disk 560. As shownin FIG. 58, the channel disk 560 includes a central aperture 584 maycommunicates with the adapter cannula 532, which communicates with themedicament cartridge 12 of the pen injector 50. The channel disk 560also includes a plurality of openings 588 therethrough respectivelycorresponding to the plurality of needles 552, and a plurality of radialchannels 592 connected with the central aperture 504 and alsorespectively corresponding to the plurality of needles 552.

FIG. 59 is a top perspective view in cross-section of the adapterchannel 564, which has a plurality of openings 596 through a floorthereof and the corresponding plurality of radial channels 600 fluidlycommunicating with the plurality of openings 596. The plurality ofopenings 596 and the plurality of radial channel 600 respectivelycorrespond with the plurality of needles 552. Referring to FIGS. 58 and59, together, the radial channels 592 and 600 cooperate to form areservoir 604.

Referring back to FIGS. 55 and 56, prior to selection of a needle 552,the septum portions 572 of needles 552 pass through the septum 568, theopenings 596 and the openings 588, such that the proximal ends of theseptum portions 572 are disposed within the top septum 556, whichprovides a sterile barrier for the proximal ends of the septum portions572. The previously-described sterility barriers serve as sterilebarriers for the distal ends of the patient portions 580 of theplurality of needles 552.

Once the needle 552 is selected, distal displacement of the outerhousing 536 distally displaces the selected needle 552. At the end ofthe distal stroke of the needle 552, the septum portion 572 of theselected needle (and thus, the patient portion 580) fluidly communicateswith the reservoir 604, thereby permitting injection of the medicamentfrom the medicament cartridge through the adapter cannula 532, theadapter 528, the reservoir 664, and the selected needle 552 into thepatient. Subsequently, along with the proximal displacement of the outerhousing 536, the selected needle 552 displaces proximally to re-sheaththe patient portion 580 within the inner housing 540 and re-sheath theproximal end of the septum portion 572 within the top septum 556.

According to one embodiment, a given needle 200 or 552 is not reusableafter a user has rotated the outer housing 104 or 536 to select the nextneedle. To accommodate emergency situations, however, it is helpful fora user to be able to access and reuse, for example, a final one of theplurality of needles. FIG. 60 illustrates a final needle 620 for usewith the changing device 100 or the changing device 520. As shown inFIG. 60, the final needle 620 has a structure 624 for interacting withthe needle selection mechanism to permit repeated access to the finalneedle 620. According to one embodiment, the structure 624 is an upperneedle protrusion 624. Unlike the needle 200 shown in FIG. 6, however,the upper needle protrusion 624 of the final needle 620 has a chamfer628 on a distal surface thereof. Accordingly, with such a chamfer 628,the beveled portion 300 of the protrusion 264, for example, can bedisplaced proximally relative to the final needle 620, so that the finalneedle 620 can again be selected for distal displacement and thus,re-use.

Although the previously-described embodiments refer to pen injectiondevices, it will be understood by one skilled in the art thatembodiments of the present invention may also be used with othermedicament injection devices, such as syringes.

Changing typical pen needle assemblies for pen injectors takes up to sixuser steps to install and remove from the pen; in addition, the user maybe vulnerable to accidental needlesticks when manipulating the penneedle assembly. Embodiments of the present invention provide novelmeans for changing needles in a contained, efficient, and user-friendlymanner. An array of needles is contained within the changing device,attached to the end of a typical pen, or likewise, integrated into aspecially designed delivery device. The changing device itself has anexterior twisting dial (e.g., outer housing 104) for the user to engagea new needle for use. The dial can then be pushed in the distaldirection with respect to the pen injector. As the user pushes the dialor outer housing distally, the proximal end of the new needle pierces aseptum adapter, opening a fluid path to the pen cartridge, and thedistal end of the new needle is exposed for insertion into the deliverysite. When the delivery is complete, the user simply pulls the dialproximally, sheathing the exposed needle. The user can now advance thedial to the next needle and start the process again.

In some embodiments of the present invention, the adapter changes thedirection of the typical cartridge septum, which normally faces thedistal end of a typical injection pen. This adapter clamps a ring shapedseptum about the pen diameter while tapping the cartridge septum with anintegrated needle. Between this ring-shaped septum, which facesproximally up the pen, and the cartridge tap, a small fluid cavity iscreated. The needles are hook-shaped, meaning the end used to pierce thering shaped septum are bent 180° so that they extend in substantiallythe same direction as the distal end of the needle. This shape permitsthe needles to be stored circumfrentially about the pen. According toone embodiment, prior to selection, the needles are all partiallyinserted into the reversed septum. According to another embodiment,prior to selection, none of the needles are inserted into the reversedseptum, but each needle is ready to be inserted into the reversed septumupon selection thereof. This partial insertion acts as a sterilitybarrier, as well as a means of solidly fixing the needles in the device.As the radial dial turns, the radial dial's selector feature engagesindividual needles. By moving the dial vertically down the pen, thehook-shaped needle pierces the reversed septum and exposes itselfthrough another septum integrated in the distal end of the device.Needles are sheathed, and returned to their nominal storage state bypulling back on the dial or outer housing.

Currently there are no fully automatic needle changing devices on themarket. There are many examples of devices that aid with individualsteps of the needle changing process, including needle storage, needleattachment, needle removal, and needle disposal, but none of thesedevices integrate the needle changing processes into one device.

By storing the needles around the circumference of the pen, a user canavoid carrying bulky injection “kits”. With an integrated device, allneedles can be stored with the pen. In addition, according to oneembodiment, the device stores new needles in a sterile manner, storingneedles within septa that act as sterility barriers. This allows storageof used needles alongside the new ones. Therefore, the device can alsofunction as a used sharps container.

Cumbersome and potentially dangerous needle attachment is made easierfor the user. The interfaces of embodiments of the present invention aremore user friendly than the typical pen needle hub. With this invention,the user interfaces with a dial, advancing to new needles with a twist,and piercing the septum with an upward pull on the pen injector (whichis a push downward on the outer housing or dial). With current needlesused for pen injectors, the user must remove the top of the needlecontainer, twist the needle onto the pen, remove the needle container,and then finally remove a needle cap. While there are some needlestorage devices that aid in placing the needle hub on the pen, the userstill must remove needle hub packaging, including the inner needlesheath, to place a needle hub onto a typical pen injector and ready itfor injection. With embodiments of the current invention, the typicalfour meticulous steps with small sharp needle hubs can be reduced tothree intuitive steps with ergonomic user interfaces.

Needle removal and disposal can also be simplified with embodiments ofthe present invention. There are many devices that aid in removingneedles from pens after use, including needle clipping devices andsharps containers that pull the needle from the pen body. But thesedevices are more cumbersome to use than embodiments of the presentinvention. With embodiments of the present invention, the user cansimply slide a dial proximally up relative to the pen, automaticallyre-sheathing the exposed needle.

Embodiments of the present invention can integrate the needle changingprocess into a single device. Needle storage, needle attachment, needleremoval, and needle disposal can now be accomplished via a singlesystem. In some embodiments, hook-shaped needles are located around theperimeter of the device, inserted into a reversed septum. In otherembodiments, straight needles are similarly arrayed around the perimeterof the device. When the user turns the external dial, a verticalmovement feature is moved to a new needle. As the user pushes distallyon this dial, the selected needle pierces the reservoir septum, openinga fluid path. In addition, the needles can be embedded in a distalseptum (sterility barrier). The selected needle pierces through thedistal septum, exposing itself for injection. The needle is pulled backinto the device when the user pulls upward on the dial.

According to one embodiment, the manual needle retraction can be madeautomatic by having a needle shield (not shown) incorporated into thedevice as a means of sensing medication delivery. According to anotherembodiment, the needle shield can act as a safety and prevent fluid flowfrom the distal end of the needle until the shield is compressed backinto the device. According to yet another embodiment (not shown),compressing the needle shield back into the device can trigger a springreturn, which automatically retracts the needle into the device.

In embodiments of the present invention, the overall needle assembly canbe made from a plastic tube with metal needles attached to both ends andfeatures to activate the needles to pierce the septa. In contrast, in anembodiment in which a straight metal needle is bent to the desiredshape, at the point of the bend, and when the bend radii are small, theinner diameter of the needle can be slightly reduced. This narrowing ofthe inner diameter can result in a rise of injection pressure. The bendradii of the exemplary embodiments of the present invention, however,are likely large enough to minimize such an injection pressure rise. Asan alternative, a larger inner diameter metal needle may be employed toachieve the desired inner diameter subsequent to bending, but thisportion may increase the expense of manufacturing the device and mayresult in an outer needle diameter undesirable for the patient.Nevertheless, in an embodiment with a plastic tube and metal needles,high injection pressures can be prevented, the desired outer needlediameter needle implemented, and the needle assembly manufactured moresimply.

In an exemplary embodiment of the present invention, each new needle(i.e., prior to being used for an injection) stored in the needlechanging device is individually sterile, thereby preventingcontamination of a new needle by a used needle. For example, a sterilitybarrier is provided for each new needle.

In another exemplary embodiment of the present invention, each usedneedle remains accessible such that the user has access to the usedneedles in case of an emergency. Alternatively, of the used needles,only the last-used needle is always accessible, thereby providing anavailable needle in case of emergency.

Although only a few embodiments of the present invention have been shownand described, the present invention is not limited to the describedembodiments. Instead, it will be appreciated by those skilled in the artthat changes may be made to these embodiments without departing from theprinciples and spirit of the invention, the scope of which is defined bythe appended claims and their equivalents.

What is claimed is:
 1. An apparatus for storing and changing needles forconnection with a medicament delivery device, the apparatus comprising:a housing having a floor disposed at a distal end thereof; a needleholder disposed within the housing, for fluidly connecting with themedicament container of the medicament delivery device; a plurality ofneedles displaceably disposed on the needle holder; a user interfacedisposed on the housing to individually select one of the plurality ofneedles and displace the selected needle; and a plurality of sterilitybarriers for ensuring sterility of a patient portion of each needleprior to exposure to an outside of the apparatus; wherein each sterilitybarrier comprises: a needle hub disposed around a portion of the patientportion of the needle; and an introducer, adapted to slide relative tothe needle hub, the introducer having a distal cutting tip adapted tocut an opening to access the outside of the apparatus through the floor.2. The apparatus according to claim 1, wherein: the floor is sterile;the introducer is adapted to cut the opening in the sterile floor; theintroducer has a proximal shoulder adapted to engage the sterile floorsubsequent to cutting the sterile floor; and the sterility barrier isadapted such that subsequent to engagement between the proximal shoulderand the sterile floor, further distal displacement of the needledistally displaces the needle hub relative to the introducer and exposesan end of the patient portion to the outside of the apparatus.
 3. Theapparatus according to claim 1, wherein: each sterility barrier furthercomprises a boot adapted to slide relative to the introducer, the boothaving a sterile floor at a distal end thereof; the introducer has aproximal shoulder adapted to engage the sterile floor of the boot;wherein the sterility barrier is adapted such that during distaldisplacement of the needle, subsequent to contact between the boot andthe floor of the inner housing, the introducer distally displacesrelative to the boot and cuts the opening in the sterile floor of theboot; and wherein the sterility barrier is adapted such that subsequentto engagement between the proximal shoulder and the sterile floor of theboot, further distal displacement of the needle distally displaces theneedle hub relative to the introducer and exposes an end of the patientportion to the outside of the apparatus.
 4. An apparatus for storing andchanging needles for connection with a medicament delivery device, theapparatus comprising: a housing having a floor disposed at a distal endthereof; a needle holder disposed within the housing, for fluidlyconnecting with the medicament container of the medicament deliverydevice; a plurality of needles displaceably disposed on the needleholder; a user interface disposed on the housing to individually selectone of the plurality of needles and displace the selected needle; and aplurality of sterility barriers for ensuring sterility of a patientportion of each needle prior to exposure to an outside of the apparatus;wherein each sterility barrier comprises a boot disposed at a distal endof the patient portion of the needle.
 5. The apparatus according toclaim 4, wherein the sterility barrier is adapted such that duringdistal displacement of the needle, subsequent to contact between theboot and the floor of the housing, the needle pierces a distal end ofthe boot and passes through an opening in the floor of the innerhousing, exposing an end of the patient portion to the outside of theapparatus.
 6. The apparatus according to claim 4, wherein each sterilitybarrier further comprises: a needle hub disposed around a portion of thepatient portion of the needle; and an introducer, slidable relative tothe needle hub; wherein the boot is adapted to slide relative to theintroducer, the boot having a sterile floor at a distal end thereof;wherein the introducer has a distal cutting tip adapted to cut a portionof the sterile floor, and a proximal shoulder adapted to engage theboot; wherein each sterility barrier is adapted such that during distaldisplacement of the needle, subsequent to contact between the boot andthe floor of the housing, the introducer distally displaces relative tothe boot and cuts the sterile floor; and wherein each sterility barrieris adapted such that subsequent to engagement between the proximalshoulder and the boot, further distal displacement of the needledistally displaces the needle hub relative to the introducer and exposesan end of the patient portion to the outside of the apparatus.